高龄大鼠血管钙化及血管壁骨桥蛋白、骨钙素表达的研究

目的研究高龄大鼠血管钙化的发生情况,以及骨桥蛋白(osteopontin,OPN)、骨钙素(osteocalcin,OC)在高龄大鼠动脉血管壁表达的变化。方法选择20只20月龄的SD大鼠为实验组,20只3月龄的SD大鼠为对照组,取大鼠的主动脉条、心脏和肾组织备检。HE染色观察血管形态,Von Kossa染色判断钙盐沉积程度,免疫组化和蛋白质印迹法(Western-blot)测定血管壁OPN、OC的表达情况。结果实验组大鼠血管平滑肌细胞排列紊乱,中膜层厚度增加,弹力板断裂,血管纤维化程度增高;对照组大鼠血管内膜内皮细胞、血管平滑肌细胞排列整齐,弹力板完整。实验组大鼠的大动脉和微小动脉内均可见钙盐沉积,对照组动脉未见钙盐沉积。实验组大鼠血管壁OPN、OC的表达较对照组明显上调(P0.05)。结论血管中膜钙化可能是血管老化的病理表现,血管钙化的形成可能与骨形成相关蛋白OPN和OC的表达上调有关。

Research on the vascular calcification and the expressions of osteopontin and osteocalcin in the arterial wall of aged rats

Objective This study was designed to investigate the morphology of vascular calcification in aged rats and the expressions of osteopontin and osteocalcin in the arterial wall of old rats. Methods 20 20-month-old SD rats were recruited in experimental group and 20 3-month-old SD rats were recruited in control group. Aorta, heart and kidney of the rats were collected for assay. HE staining and Von Kossa staining were used to determine the vascular calcification. The expressions of OPN and OC in vascular wall were tested by Immuno-histochemistry and Western-blot. Results In the experimental group, vascular smooth muscle cells are disordered arrangement, thickness of membrane layer is increased, elastic plate fracture and the vascular fibrosis is increased. In the control group, vascular endothelial cells and smooth muscle cells are arranged in neat, elastic plate is complete. In the experimental group, the large artery and small artery were observed the calcium salt deposits. In the control group,arteries were not observed calcium salt deposits. Compared with the control group, the expressions of OPN and OC were significantly increased in the experimental group (P<0.05). Conclusions Vascular medial calcification may be pathological features of vascular aging. Vascular calcification may be related with the up-regulated expression of bone-associated protein OPN and OC.